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Overview of Smart Tracking Course Recording System

Overview of Smart Tracking Course Recording System

Sep 23 2014

The course recording system represents a significant shift in teaching methods, serving three crucial functions:

  1. Teachers can review recorded videos to correct their teaching actions and content.
  2. Absent students can access the teacher's instruction from the class.
  3. Students can use videos for reviewing course materials.

While there are numerous vendors in the market planning course recording systems, each with its design philosophy, the ultimate goal is to achieve optimal results for both schools and students in this evolving teaching model.

Course recording systems began developing basic prototypes around the year 2000, with content similar to current systems. These systems typically include teacher videos and instructional materials compiled into a course video. The videos are then accessed through the school's website with the vendor's playback interface. However, challenges arose due to the limitations of the environment and bandwidth at that time.

Initially, video quality was limited to 300,000 pixels using a computer's camera, restricting close-up shots of teachers. In recent years, the rise of Massive Open Online Courses (MOOCs) globally has brought increased attention to course recording solutions. The IT industry's involvement has equipped course recording with more electronic computing programs and software. Major broadcasting companies have also recognized the assistance course recording provides to future students, leading several well-known broadcasting industries to combine broadcasting skills with IT electronic computing to create flawless recording systems. The following is a system that integrates IT and broadcasting for course recording, exploring its unique features in depth.

The Smart Tracking Course Recording System comprises multiple PTZ cameras, panoramic cameras, microphone arrays, image analysis servers, switchers, location pointers, and recording systems. Operators use the location pointer to guide the image analysis server in controlling PTZ cameras to track specific targets. Simultaneously, the microphone array captures sound from the specified targets, generating audio data. The switcher receives audio data, PTZ camera, and panoramic camera image data, processes them, and produces the final audio-visual data. Finally, the recording system receives the ultimate audio-visual data for recording. The system can also display the image of the final audio-visual data on a monitor and play the sound through speakers. Therefore, it achieves semi-automatic image tracking, monitoring, and recording functions suitable for multi-participant locations.

For live class recordings in remote teaching, interaction between teachers and students during class, such as teachers posing questions and assigning specific students to answer or enthusiastic students responding, requires constant adjustment of the camera's distance, focus, and multiple switches between the teacher and different students. Thus, professional directing is essential to achieve a live teaching audio-visual effect.

The Smart Tracking Course Recording System provides automatic tracking core technology without the need for directors or camera operators. Users can independently control the entire recording process manually through handheld devices, achieving semi-automatic image tracking and recording objectives, thus saving manpower. The system includes multiple PTZ cameras, a panoramic camera, a microphone array, an image analysis server, a switcher, a location pointer, and a recording system, enabling semi-automatic image tracking while simultaneously recording audio and video.

 

The PTZ cameras are positioned at different locations in specific areas, allowing them to capture and track specific targets, generating individual PTZ image data. The panoramic camera is strategically placed to capture images covering the entire area, producing panoramic image data. The microphone array, consisting of multiple microphones positioned at different locations, receives sound to generate audio data.

The location pointer comprises multiple buttons, each generating corresponding control commands when pressed by the operator. The location pointer wirelessly transmits control commands to the image analysis server. The image analysis server, based on control commands, controls the rotation, tilt, and zoom actions of the PTZ cameras to align with specific targets. Simultaneously, the image analysis server receives PTZ image data from the PTZ cameras and performs image analysis to confirm the specific target. The image analysis server generates and transmits control signals related to the PTZ cameras.

The switcher receives audio data from the microphone array and PTZ image data from the PTZ cameras, as well as panoramic image data from the panoramic camera. Based on control signals from the image analysis server, the switcher switches between PTZ camera PTZ image data and audio data, or combines panoramic image data, generating the final audio-visual data. This data is transmitted to the recording system, which receives and processes it for recording, achieving semi-automatic operation for intelligent monitoring, tracking, and recording.

Furthermore, the recorded video can be displayed on at least one monitor and played through at least one set of speakers, providing real-time playback functionality for convenient monitoring.

Therefore, the Smart Tracking Course Recording System is suitable for locations with multiple participants, especially for recording or live streaming digital course content or MOOCs (Massive Open Online Courses). In this system, the teacher can use the location pointer to guide the PTZ camera to track a student speaking and record the session. After the student has finished speaking, the teacher can use the location pointer to return the PTZ camera to a predefined area, such as the teacher. In this way, the teacher takes on the role of a director, completing the camera's rotation, image capture, and recording tasks, achieving the semi-automatic tracking objective.

The Smart Tracking Course Recording System combines an AI-based fully automatic smart director and a manual control director system, with the operation determined by the POINTER switch:

  1. When the POINTER switch is off, the system activates the AI-based fully automatic smart tracking mode, including:

    • Static camera and PTZ camera calibration technology
    • Detection of student speaking events
    • Multi-angle face detection technology
    • Teacher movement detection and tracking technology

    The fully automatic system detects and locates student speakers and automatically tracks the teacher in the classroom. Using static camera and PTZ camera calibration technology, it provides automatic close-ups of speaking students and the teacher, along with microphone recording, creating a natural classroom broadcasting scenario.

  2. When the POINTER switch is on, the system activates the manual control director system:

    • The manual control director system uses the teacher's handheld POINTER as a guide to student positions.
    • Student position detection integrates POINTER pointing technology with teacher movement detection and tracking technology.
    • When the teacher points the POINTER at a speaking or designated student position, the PTZ camera automatically performs image close-ups and microphone recording based on pre-defined control settings.

The POINTER utilizes two sensors, G-SENSOR and E-SENSOR, to calculate the global positioning angle and introduces error compensation technology for pointing angle accuracy even during flips. The POINTER then returns the angle to the director system.

 

Smart Tracking Course Recording System Features

  1. Combining computer vision technology and sensing technology to develop a highly intelligent directing system, breaking through the traditional manual directing mode.
  2. POINTER control function, empowering teachers with control over classroom recording.
  3. Interactive recording between teachers and students, offering a departure from monotonous e-learning course recording.
  4. Smart face tracking mode without the need for wearing tracking devices.
  5. Gentle camera movements, unlike rapid infrared shaking modes, providing smooth output images for effortless viewing.
  6. Synchronized control of cameras, local audio recording, directing switches, and recording activation functions.

The integration of IT and broadcasting allows the course recording system to be more user-friendly and technologically advanced. This marks the beginning of a new phase in school education, and we continue to observe the development of this transformation.